The issue of canon (i.e. manga + BoG only) Cell being able to bust the solar system has been a hot debate for a long, long time. It's been going around in circles with no end in sight. I have put together a calculation which debunks this statement as JUST a hyperbole.
Before anybody replies to this, either in agreement or in argument, I would like them to go through the entire post properly.
So, why isn't Cell a solar system buster?
Before coming to that, we need to determine the energy needed to actually destroy the solar system. For that purpose, I would like to redirect everybody to this calculation. Long story short, after taking all factors into account, the energy required to destroy the mass of the solar system is 5.5 x 10^31 tons of TNT if using a purely focused blast, 5.09 x 10^37 tons of TNT if a unidirectional blast which encompasses the entire volume (Kamehameha's Area of Effect is ALWAYS unidirectional).
So the energy required to destroy the solar sytem is 5.09 x 10^37 tons of TNT.
Now that the required energy output has been established, let us disprove exactly why Cell isn't a solar system buster. The answer to that is very simple: even SSJ3 Goku in BoG cannot produce the required energy, and he is way above Cell in terms of raw power output.
Now I will proceed to calculate BoG SSJ3 Goku's energy output. Bills states in the movie Battle of Gods about base Goku being weaker than 100% Frieza.
1% Frieza easily one-shotted planet Vegeta. However, 100% Frieza is at best a Star buster (many people believe him to be large planet only, but I'm giving him a huge benefit of doubt). The energy levels required to destroy a star are stated right here. The maximum energy to destroy a star is 10 XKt of TNT (note: this is Large Star Level, which Frieza is nowhere close to).
10 XKt = 10 x 10^33 tons of TNT => 10^34 tons of TNT
This energy output is greater than BoG base Goku's. Taking into account Goku's SSJ3 transformation, which has a 400x multiplier (for the uninitiated: 50x for SSJ1, 2x for SSJ2, 4x for SSJ3), the resulting energy output could from SSJ3 Goku would be at most 400x
=> 400 x 10^34 = '4 x 10^36 'tons of TNT
'4 x 10^36 << '5.09 x 10^37
So there you have it, people. Even after giving BoG base Goku a massive energy boost (by taking him to be Large Star Level, which he clearly is NOT), SSJ3 Goku is nowhere near solar system busting. Unless somebody is stupid enough to argue that Cell surpasses BoG SSJ3 Goku, I think it's safe to presume that Cell is NOT a solar system buster.
Note: Please check for any corrections and feel free to point them out.